Dear all,

Hope you all have a good day!

While looking into the COMPASS III force field, I found that n2a and n3a have the same description - nitrogen, sp2, aromatic.

This seemed strange at first, but on second thought, I guessed that aromaticity requires pi-electrons, which originate from the p-orbitals.

Therefore, n2a and n3a share the same description, and the only difference between them is whether the nitrogen forms two or three bonds.

Could you please check if my understanding is correct?

Thank you always.

Best regards,

Rakhoon Choi